1. Field of the Invention
The present invention is in the field of a method and apparatus for reducing the agitation of sizing liquid caused by energy being delivered into the pond by the high speed surfaces of the rolls and paper. Specifically, the sizing pond is isolated from the high speed surfaces by one or more sets of baffles which are positioned between the traveling web and the rotating roll.
2. Description of the Prior Art
In a typical sizing operation, a pond of the sizing material which usually consists of an aqueous latex of relatively high viscosity is provided at the nip of a pair of coacting, oppositely rotating rolls. The paper web is directed through the coating nip for simultaneous application of the sizing material on both surfaces. Experience in operating such size applicators shows that at high speed the pond of sizing liquid between the paper and the rolls of the size press becomes so agitated that the material is actually thrown from the pond. The kinetic energy of the moving surfaces induces rapid circulation of the coating. Both roll surfaces and the paper are moving toward the nip, pulling the size composition with them. This size solution must then return or circulate and when the upward velocity of the size liquid away from the moving surfaces becomes sufficiently high, the coating will break through the surface tension of the pond and will cause splashing.